Agitating device for vacuum cleaner filters



Dec. 6, 1955 ow 2,725,953

AGITATING DEVICE FOR VACUUM CLEANER FILTERS Filed May 9, 1952 3 Sheets-Sheet l INVENTOR.

Dewey M 0014/ WUM. 4

A TTORNE Y Dec. 6, 1955 D. M. DOW 2,725,953

AGITATING DEVICE FOR VACUUM CLEANER FILTERS Filed May 9, 1952 3 Sheets-Sheet 2 IN V EN TOR.

By DEWEY /YZ Dow album 61%.

A 7' TORNE Y Dec. 6, 1955 D. M. DOW

AGITATTNG DEVICE FOR VACUUM CLEANER FILTERS 3 Sheets-Sheet 5 Filed May 9, 1952 A TTOENEY 50 MD M W m WMWMQM,

United States Pater:

AGITATlNG DEVICE FOR VACUUM CLEANER FILTERS Dewey M. Dew, Toledo, Ohio, assignor to Air-Way Industries, Inc, a corporation of Delaware Application May 9, 1952, Serial No. 286,945 7 Claims. (Cl. 18358) This invention relates to portable vacuum cleaners wherein the dust and dirt is separated from the air stream by a filter medium, such as porous paper or similar sheet material, and an object is recurrently to agitate or vibrate the filter medium automatically, for example prior to the start of the working or cleaning period and at the end thereof, in order to insure that the filter operates at its maximum efiiciency at all times by freeing it from particles which would otherwise militate against proper cleaning operation.

Other objects and advantages, of the invention will hereinafter appear, and for purposes of illustration but not of limitation, an embodiment of the invention is shown on the accompanying drawings, in which Figure 1 is a side elevation partly in section, of a vertical tank type vacuum cleaner embodying the invention with the agitating means shown in full lines in operative position and in broken lines in inoperative position;

Figure 2 is an enlarged fragmentary view showing the agitating arms and associated parts;

Figure 3 is an enlarged sectional view substantially on the. line 3-5 of Figure 1;

Figure 4 is a vertical elevation of an alternate form of vacuum cleaner, parts being broken away for purpose of clarity;

Figure 5 is a bottom plan view of the cloth bag and associated parts; and

Figure 6 is a fragmentary sectional view of the bag and mounting and showing in section another means for vibrating the bag.

Referring to Figures 1 to 3 of the drawings, the vacuum cleaner comprises a lower tank or dirt receptacle 10 on which is supported a cover 11. The cover 11 carries a dome-shaped housing 12 containing the usual electric motor operating a suction fan unit. The electric motor shaft has an extension 13 which depends from the housing 12 and carries on its lower end a fixed bracket 14 extending radially from the shaft extension. Pivoted at its inner ends to the bracket 14 is, a pairof arms 15 which curve downwardly and outwardly from the bracket. A leaf spring16 is associated with each arm and one end of each spring is fixed to the bracket 14 and thefree end portion bears against the adjacent arm urging it to its downward position. In this instance, rubber pads 17 are secured to the under side of the free ends of the arms 15.

Although the arms are preferably of metal carrying rubber pads and loading springs as above indicated, they may be simple leaf springs with rubber pads attached, or the bracket 14 and arms 15 may be integral, molded of rubber and self-loading, designed to offer minimum air resistance under high speed rotation of the shaft extension 13.

On the flange of the cover 11 is a sealing gasket 18 and on the mouth of the tank 10 is a sealing gasket 19, and clamped between these gaskets by one or more springtensioned latch members 20 is a wire mesh screen 21 completely covering the mouth of the tank 10. On the 2,725,953 Patented Dec. 6, 1955 use under side of the screen 21 and abutting thereagainst is a filter fabric or sheet 22 of air pervious textile or the like for permitting the passage of air therethrough but preventing the passage of dirt or other foreign substances. The filter sheet 22 is clamped between gaskets 18 and 19 interposed between the screen 21 and crossed wires 23 which are suitably connected to the tank 10.

Attached to the upper surface of the screen 21 in any suitable manner is an annulus 24 having a series of spaced radially extending ribs or raised sections 25.

-It will be understood that normally the arms are in engagement with the ribbed upper face of the annulus 24-. However, when the vacuum cleaner is energized so that the shaft extension 13 is rotated, the pads 17 on the free end portions of the arms 15 revolve over the ribbed surface of the annulus thereby imparting vibratory movement to the screen 21 and consequently, to the filter sheet 22, violently agitating the latter to shake off or remove any dirt or foreign particles which may have adhered to it. The dirt drops by gravity then into the tank 10. However, as soon as the electric motor has developed sufficient speed, the arms 15 swing outwardly or upwardly against the tension of the leaf spring 16, by centrifugal force so that in the normal operation of the vacuum cleaner, the arms 15 do not interfere or impose any resistance to the operation of the suction fan operating motor. When the motor is deenergized and after the shaft extension 13 operates at a sufliciently reduced speed, the arms 15 will again engage the ribs 25 on the annulus 24 and again impart agitation to the screen and filter sheet. Thus the agitation of the filter sheet takes place automatically at the start and during the stopping of the operation of the vacuum cleaner when there is a minimum pressure difi'erential between the inner and outer surfaces of the filter medium, and a minimum of air flow through the filter. In this manner an efficient cleaning of the filter sheet is effected automatically.

it will be observed that a nozzle is provided on the tank iii to provide an inlet conduit or air. A flexible hose carrying the usual nozzle 26.

The alternate form of the invention shown on Figures 4 to 6, comprises an elongate housing 27 in which is disposed an electric motor generally designated at 23, the same including a driven shaft 29 which has a head carry ing a pair of spring-loaded pivoted arms 36. The arms 30 are engageable with the radially ribbed or corrugated annulus 31 for imparting vibrational movements thereto when the electric motor starts its operation and as it is stopping, similar to that hereinabove described. The annulus 31 is carried on the under side of a pair of Crossed metallic straps 32 which are secured together-t0 form a unitary structure. A cloth bag 33 having a closed bottom is adapted to seat on the crossed strap framework 32. As shown, the outer ends of the straps 32 are somewhat hook shaped as indicated at 3- 3, and fitting within the bag 33 on the bottom portion thereof is a split wire ring 35, which may be disposed forces the edge portion of the bag into the hook portions 3 5, thus holding the bottom of the bag securely in the desired position. With its lower end resting upon the hooked portions, as indicated in Figure 6, and incurbracing relation to the walls of the bag 33 is a helical spring 37 which extends for the full length of the bag, the upper end of the spring abutting against a disc 38 to which the upper end of the bag is connected. The spring 37 keeps the bag surface taut and serves to transmit the vibrations from the annulus 31 to all surfaces of the bag, thus to shake or vibrate from the surfaces of the bag any dirt or dust particles which might cling thereto. The outer edge portion of the disc 38 is clamped beshaped within a sheath Edand which tween gaskets 39 and 40, so that when the pivoted lid or cover 41 is closed, as indicated in Figure 4, the disc is securely retained in position.

It will be understood that a flexible hose is connected to the nozzle on the cover 41 and the usual wand and floor tool is carried by the hose. The motor-fan unit 28 creates a suction drawing the dirt-laden air into the bag 33 and the dirt particles remain therein. From the above description, it will be manifest that the bag is vibrated throughout its length, due to the helical spring 37 and the agitating device so that maximum cleaning efficiency can be achieved. It will further be understood that if desired, a disposable porous paper bag may be arranged within the cloth bag 33, and due to the action of the air stream, the paper bag will be expanded into contact with the cloth bag so that the vibrational action will thus be transmitted to the paper bag as well and maintain the side walls of the paper bag free of clinging dirt and dust which would otherwise interfere with the porosity of the filtering medium.

An alternate form of agitating device is shown on Figure 6, in which the spring-loaded arms 30a cooperate with the cone-like annulus 31a in the manner as above described. This structure has the advantage that the spring-loaded arms 30a automatically center themselves with respect to the cone 31a. Otherwise the operation of the device is as above described.

It is to be understood that numerous changes in details of construction, arrangement, operation and choice of materials may be effected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

1. In a vacuum cleaner, a dirt receptacle, a dirt separating member arranged above said receptacle, and a shaft extension of a motor-suction fan unit, means for agitating the separating member comprising means on the shaft extension movable to inoperative position by centrifugal force, and an element associated with the separating member and with which the shaft means engages during the starting and stopping periods of rotation of the extension, said element having an irregular surface to effect such agitation when engaged by the revolving shaft means.

2. In a vacuum cleaner, a dirt receptacle, a dirt separating member arranged above said receptacle, and a shaft extension of a motor-suction fan unit, means for agitating the separating member comprising pivoted arms on the shaft extension movable to inoperative position by centrifugal force, and an element associated with the separating member and with which the pivoted arms engage during the starting and stopping periods of rotation of the extension, said element having an irregular surface to effect such agitation when engaged by the revolving pivoted arms.

3. In a vacuum cleaner, an electric motor and suction fan unit, a filter bag of air pervious sheet material, means for holding said bag taut including a helical spring intimately engaging the walls thereof, a frame including a portion having a roughened surface and secured to said 60 filter bag, agitating means on said unit comprising spring biased arms revoluble by the motor and fan unit, said spring loaded arms being normally engaged with the roughened surface when the motor and fan unit is not operating and being adapted to be disengaged from said roughened surface by centrifugal force when said motor and fan unit is operated at normal operating speed.

4. In a vacuum cleaner, :1 frame, a dust separating container supported on said frame and including one end wall comprising a flexible sheet of air-pervious material, a fiat member affixed to the outer side of said wall, said member having a plurality of outwardly disposed radial ribs therein providing a roughened surface, a motor suction fan unit supported adjacent said wall, said unit including a motor shaft having its rotational axis substantially perpendicular to said member, said shaft having a free end axially spaced from said member, a pair of spring-loaded radial arms supported on the free end of said shaft and rotating therewith, said arms being normally held by the spring loading thereof in scraping engagement with the ribs on said member whereby to vibrate said wall when said motor starts and stops, said arms being movable away from said ribs in response to centrifugal force while said motor maintains normal running speed.

5. The combination claimed in claim 4, said container comprising a filter bag having a cylindrical side wall of flexible air-pervious material and having another end wall by which said bag is supported on said frame, and a helical coil spring intimately engaging said side wall, whereby the member on said one end wall is resiliently held in position to be engaged by said arms, and whereby the vibrations of said bottom wall are transmitted throughout said bag.

6. The combination claimed in claim 4, said container comprising a filter bag having a cylindrical side wall of flexible air-pervious material, the end wall on which said ribbed member is fixed comprising the bottom wall of said bag, said bag having a top wall suspended on said frame so that the remainder of the bag hangs downwardly, and means for holding said bag taut, including a helical spring intimately engaging the side wall thereof, whereby the member on the bottom end wall is resiliently held in position to be engaged by said arms when said motor starts and stops, and whereby the vibrations of said bottom end wall are transmitted throughout said bag.

7. In a vacuum cleaner, a frame, a dust separating member supported on said frame and including a wall comprising a flexible sheet of air-pervious material, a flat member afiixed to one side of said wall, said member having a plurality of radial ribs thereon providing a roughened surface, a motor suction fan unit supported adjacent said wall, said unit including a motor shaft having its rotational axis substantially perpendicular to said member, said shaft having a free end axially spaced from said member, a pair of spring-loaded radial arms supported on the free end of said shaft and rotating therewith, said arms being normally held by the spring loading thereof in scraping engagement with the ribs on said member whereby to vibrate said wall when said motor starts and stops, said arms being movable away from said ribs in response to centrifugal force while said motor maintains normal running speed.

References Cited in the file of this patent UNITED STATES PATENTS 1,324,635 Ascoli Dec. 9, 1919 2,443,162 Hallock June 8, 1948 2,564,734 Sparklin Aug. 21, 1951 FOREIGN PATENTS 294,501 Great Britain July 23, 1928 351,588 Italy Aug. 16, 1937 456,163 France Aug. 19, 1913 

